Restore the ability to continue booting after legacy image overwrite

Before new uImage code was merged, bootm code allowed for the kernel image to
get overwritten during decompresion. new uImage introduced a check for image
overwrites and refused to boot the image that got overwritten. This patch
restores the old behavior. It also adds a warning when the image overwriten is
a multi-image file, because in such case accessing componentes other than the
first one will fail.

Signed-off-by: Marian Balakowicz <m8@semihalf.com>

12 files changed, 39 insertions, 23 deletions

diff --git a/common/cmd_bootm.c b/common/cmd_bootm.c
index 9e5ce4b38..3a0c83d2d 100644
--- a/common/cmd_bootm.c
+++ b/common/cmd_bootm.c
@@ -286,9 +286,16 @@ int do_bootm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 		debug ("image_start = 0x%lX, image_end = 0x%lx\n", image_start, image_end);
 		debug ("load_start = 0x%lx, load_end = 0x%lx\n", load_start, load_end);
 
-		puts ("ERROR: image overwritten - must RESET the board to recover.\n");
-		show_boot_progress (-113);
-		do_reset (cmdtp, flag, argc, argv);
+		if (images.legacy_hdr_valid) {
+			if (image_get_type (&images.legacy_hdr_os_copy) == IH_TYPE_MULTI)
+				puts ("WARNING: legacy format multi component "
+					"image overwritten\n");
+		} else {
+			puts ("ERROR: new format image overwritten - "
+				"must RESET the board to recover\n");
+			show_boot_progress (-113);
+			do_reset (cmdtp, flag, argc, argv);
+		}
 	}
 
 	show_boot_progress (8);
@@ -533,9 +540,17 @@ static void *boot_get_kernel (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]
 			show_boot_progress (-5);
 			return NULL;
 		}
+
+		/*
+		 * copy image header to allow for image overwrites during kernel
+		 * decompression.
+		 */
+		memmove (&images->legacy_hdr_os_copy, hdr, sizeof(image_header_t));
+
+		/* save pointer to image header */
 		images->legacy_hdr_os = hdr;
-		images->legacy_hdr_valid = 1;
 
+		images->legacy_hdr_valid = 1;
 		show_boot_progress (6);
 		break;
 #if defined(CONFIG_FIT)
@@ -890,7 +905,7 @@ static void do_bootm_netbsd (cmd_tbl_t *cmdtp, int flag,
 	 * address of the original image header.
 	 */
 	os_hdr = NULL;
-	if (image_check_type (hdr, IH_TYPE_MULTI)) {
+	if (image_check_type (&images->legacy_hdr_os_copy, IH_TYPE_MULTI)) {
 		image_multi_getimg (hdr, 1, &kernel_data, &kernel_len);
 		if (kernel_len)
 			os_hdr = hdr;
@@ -947,7 +962,7 @@ static void do_bootm_lynxkdi (cmd_tbl_t *cmdtp, int flag,
 			     int argc, char *argv[],
 			     bootm_headers_t *images)
 {
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
 	if (!images->legacy_hdr_valid) {
@@ -964,7 +979,7 @@ static void do_bootm_rtems (cmd_tbl_t *cmdtp, int flag,
 			   int argc, char *argv[],
 			   bootm_headers_t *images)
 {
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 	void (*entry_point)(bd_t *);
 
 #if defined(CONFIG_FIT)
@@ -994,10 +1009,10 @@ static void do_bootm_vxworks (cmd_tbl_t *cmdtp, int flag,
 			     bootm_headers_t *images)
 {
 	char str[80];
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
-	if (hdr == NULL) {
+	if (!images->legacy_hdr_valid) {
 		fit_unsupported_reset ("VxWorks");
 		do_reset (cmdtp, flag, argc, argv);
 	}
@@ -1014,7 +1029,7 @@ static void do_bootm_qnxelf(cmd_tbl_t *cmdtp, int flag,
 {
 	char *local_args[2];
 	char str[16];
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
 	if (!images->legacy_hdr_valid) {
@@ -1041,7 +1056,7 @@ static void do_bootm_artos (cmd_tbl_t *cmdtp, int flag,
 	int i, j, nxt, len, envno, envsz;
 	bd_t *kbd;
 	void (*entry)(bd_t *bd, char *cmdline, char **fwenv, ulong top);
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
 	if (!images->legacy_hdr_valid) {
diff --git a/common/image.c b/common/image.c
index 9e6343200..d218f2f88 100644
--- a/common/image.c
+++ b/common/image.c
@@ -983,7 +983,7 @@ int boot_get_ramdisk (int argc, char *argv[], bootm_headers_t *images,
 #endif /* CONFIG_B2 || CONFIG_EVB4510 || CONFIG_ARMADILLO */
 
 	} else if (images->legacy_hdr_valid &&
-			image_check_type (images->legacy_hdr_os, IH_TYPE_MULTI)) {
+			image_check_type (&images->legacy_hdr_os_copy, IH_TYPE_MULTI)) {
 		/*
 		 * Now check if we have a legacy mult-component image,
 		 * get second entry data start address and len.
diff --git a/include/image.h b/include/image.h
index c1a6cbb48..60fdb2bea 100644
--- a/include/image.h
+++ b/include/image.h
@@ -197,7 +197,8 @@ typedef struct bootm_headers {
 	 * then boot_get_ramdisk() and get_fdt() will attempt to get
 	 * data from second and third component accordingly.
 	 */
-	image_header_t	*legacy_hdr_os;
+	image_header_t	*legacy_hdr_os;		/* image header pointer */
+	image_header_t	legacy_hdr_os_copy;	/* header copy */
 	ulong		legacy_hdr_valid;
 
 #if defined(CONFIG_FIT)
diff --git a/lib_arm/bootm.c b/lib_arm/bootm.c
index c5e8cb3eb..6b4a80723 100644
--- a/lib_arm/bootm.c
+++ b/lib_arm/bootm.c
@@ -78,7 +78,7 @@ void do_bootm_linux (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_avr32/bootm.c b/lib_avr32/bootm.c
index b1c651ab2..5ff8c79e9 100644
--- a/lib_avr32/bootm.c
+++ b/lib_avr32/bootm.c
@@ -185,7 +185,7 @@ void do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_blackfin/bootm.c b/lib_blackfin/bootm.c
index bea11ed6d..ef4b1127f 100644
--- a/lib_blackfin/bootm.c
+++ b/lib_blackfin/bootm.c
@@ -49,7 +49,7 @@ void do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_m68k/bootm.c b/lib_m68k/bootm.c
index 6f49c3161..61f1a3648 100644
--- a/lib_m68k/bootm.c
+++ b/lib_m68k/bootm.c
@@ -96,7 +96,7 @@ void do_bootm_linux(cmd_tbl_t * cmdtp, int flag,
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_microblaze/bootm.c b/lib_microblaze/bootm.c
index fab4a5441..30a03ef35 100644
--- a/lib_microblaze/bootm.c
+++ b/lib_microblaze/bootm.c
@@ -44,7 +44,7 @@ void do_bootm_linux (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_mips/bootm.c b/lib_mips/bootm.c
index e4c139efa..f813fc583 100644
--- a/lib_mips/bootm.c
+++ b/lib_mips/bootm.c
@@ -57,7 +57,7 @@ void do_bootm_linux (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_nios2/bootm.c b/lib_nios2/bootm.c
index 0c89e9635..01f4e87cb 100644
--- a/lib_nios2/bootm.c
+++ b/lib_nios2/bootm.c
@@ -34,7 +34,7 @@ void do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_ppc/bootm.c b/lib_ppc/bootm.c
index b24a0640c..0328baddc 100644
--- a/lib_ppc/bootm.c
+++ b/lib_ppc/bootm.c
@@ -146,7 +146,7 @@ do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
@@ -639,7 +639,7 @@ static int boot_get_fdt (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 		printf ("   Booting using the fdt blob at 0x%x\n", fdt_blob);
 
 	} else if (images->legacy_hdr_valid &&
-			image_check_type (images->legacy_hdr_os, IH_TYPE_MULTI)) {
+			image_check_type (&images->legacy_hdr_os_copy, IH_TYPE_MULTI)) {
 
 		ulong fdt_data, fdt_len;
 
diff --git a/lib_sh/bootm.c b/lib_sh/bootm.c
index 3d5c3bbc9..dd32a3ed8 100644
--- a/lib_sh/bootm.c
+++ b/lib_sh/bootm.c
@@ -67,7 +67,7 @@ void do_bootm_linux (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,